1. Field of the Invention
This invention relates to an illuminated sign and more particularly relates to a house address number sign which has variable and changing multi-color illumination after dark to provide a high visibility as well as a desirable aesthetic appearance.
2. Background Art
Illuminated signs are provided such that the indicia of the signs will become clearly visible after dark. The indicia is commonly mounted at the front of an enclosure with a light source, such as an electrical light bulb, located within the enclosure behind the sign. The light source is turned on at night or when the ambient lighting is below a certain level so as to provide a back light for illuminating the indicia Illuminated house address number signs are particularly useful for rendering the house address number visible after dark. However, due to the relatively short life span of the incandescent light bulb used as a back light source, it requires changing from time to time. Since a house address number sign is normally required to be mounted at a high location on the front wall of the house in order that it can be clearly visible at a far distance, it is awkward and troublesome to change the light bulb at such high location. Also, incandescent lights have a high electrical power consumption. Attempts have been made by providing long life and low electrical consumption light emitting diode (LED) lights as a light source to alleviate the above problems. A plurality of LED lights are mounted on a support plate located behind the indicia with the LED lights arranged in the same pattern as the indicia so that when the LED lights are turned on they present an illuminated indicia or number. A main drawback of such construction is that when one or several LED lights become inoperative, the indicia becomes unevenly illuminated such that the indicia or number is no longer clearly legible or identifiable. Some LED light illuminated signs resolve the above problem by mounting a plurality of LED lights on the side walls of the enclosure such that the indicia is illuminated by reflected light from the LED lights. However, the reflection means are not effective in providing a strong desirable illumination of the indicia. Furthermore, only LED lights providing lighting of a single color are provided such that the illumination is not attractive, and the sign does not provide any aesthetic value to the house.